﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using ICSharpCode.SharpZipLib;
using ICSharpCode.SharpZipLib.Zip;
using ICSharpCode.SharpZipLib.Checksums;

     /// <summary>
     /// 适用与ZIP压缩
     /// </summary>
     public class ZipHelper
     {
         #region 压缩
 
          /// <summary>
        /// 递归压缩文件夹的内部方法
          /// </summary>
          /// <param name="folderToZip">要压缩的文件夹路径</param>
          /// <param name="zipStream">压缩输出流</param>
          /// <param name="parentFolderName">此文件夹的上级文件夹</param>
         /// <returns></returns>
          private static bool ZipDirectory(string folderToZip, ZipOutputStream zipStream, string parentFolderName)
          {
              bool result = true;
              string[] folders, files;
              ZipEntry ent = null;
              FileStream fs = null;
              Crc32 crc = new Crc32();
  
              try
              {
                  ent = new ZipEntry(Path.Combine(parentFolderName, Path.GetFileName(folderToZip) + "/"));
                zipStream.PutNextEntry(ent);
                zipStream.Flush();
 
                files = Directory.GetFiles(folderToZip);
                 foreach (string file in files)
                 {
                     fs = File.OpenRead(file);
 
                     byte[] buffer = new byte[fs.Length];
                  fs.Read(buffer, 0, buffer.Length);
                     ent = new ZipEntry(Path.Combine(parentFolderName, Path.GetFileName(folderToZip) + "/" + Path.GetFileName(file)));
                     ent.DateTime = DateTime.Now;
                     ent.Size = fs.Length;
 
                     fs.Close();
 
                     crc.Reset();
                     crc.Update(buffer);
 
                    ent.Crc = crc.Value;
                     zipStream.PutNextEntry(ent);
                    zipStream.Write(buffer, 0, buffer.Length);
                 }
 
             }
             catch
             {
               result = false;
              }
            finally
             {
                 if (fs != null)
                 {
                    fs.Close();
                    fs.Dispose();
                }
               if (ent != null)
                {
                    ent = null;
                }
                 GC.Collect();
                GC.Collect(1);
             }

             folders = Directory.GetDirectories(folderToZip);
             foreach (string folder in folders)
                 if (!ZipDirectory(folder, zipStream, folderToZip))
                    return false;
 
            return result;
        }

        /// <summary>
         /// 压缩文件夹 
         /// </summary>
        /// <param name="folderToZip">要压缩的文件夹路径</param>
         /// <param name="zipedFile">压缩文件完整路径</param>
         /// <param name="password">密码</param>
        /// <returns>是否压缩成功</returns>
        public static bool ZipDirectory(string folderToZip, string zipedFile, string password)
        {
             bool result = false;
             if (!Directory.Exists(folderToZip))
            return result;
 
            ZipOutputStream zipStream = new ZipOutputStream(File.Create(zipedFile));
           zipStream.SetLevel(6);
           if (!string.IsNullOrEmpty(password)) zipStream.Password = password;

             result = ZipDirectory(folderToZip, zipStream, "");
 
            zipStream.Finish();
           zipStream.Close();

             return result;
         }

        /// <summary>
        /// 压缩文件夹
        /// </summary>
         /// <param name="folderToZip">要压缩的文件夹路径</param>
        /// <param name="zipedFile">压缩文件完整路径</param>
        /// /// <returns>是否压缩成功</returns>
         public static bool ZipDirectory(string folderToZip, string zipedFile)
       {
            bool result = ZipDirectory(folderToZip, zipedFile, null);
             return result;
        }
 
         /// <summary>
        /// 压缩文件
      /// </summary>
      /// <param name="fileToZip">要压缩的文件全名</param>
        /// <param name="zipedFile">压缩后的文件名</param>
         /// <param name="password">密码</param>
        /// <returns>压缩结果</returns>
        public static bool ZipFile(string fileToZip, string zipedFile, string password)
        {
            bool result = true;
            ZipOutputStream zipStream = null;
            FileStream fs = null;
             ZipEntry ent = null;

            if (!File.Exists(fileToZip))
                 return false;

            try
             {
          fs = File.OpenRead(fileToZip);
                 byte[] buffer = new byte[fs.Length];
                 fs.Read(buffer, 0, buffer.Length);
                 fs.Close();
 
                 fs = File.Create(zipedFile);
                zipStream = new ZipOutputStream(fs);
                if (!string.IsNullOrEmpty(password)) zipStream.Password = password;
                 ent = new ZipEntry(Path.GetFileName(fileToZip));
                zipStream.PutNextEntry(ent);
                 zipStream.SetLevel(6);

                zipStream.Write(buffer, 0, buffer.Length);

            }
            catch
            {
                result = false;
            }
            finally
            {
                 if (zipStream != null)
                {
                    zipStream.Finish();
                    zipStream.Close();
                }
                if (ent != null)
                {
                    ent = null;
                }
                if (fs != null)
                {
                    fs.Close();
                    fs.Dispose();
               }
            }
             GC.Collect();
            GC.Collect(1);

             return result;
         }
 
         /// <summary>
         /// 压缩文件
         /// </summary>
        /// <param name="fileToZip">要压缩的文件全名</param>
         /// <param name="zipedFile">压缩后的文件名</param>
         /// <returns>压缩结果</returns>
        public static bool ZipFile(string fileToZip, string zipedFile)
         {
            bool result = ZipFile(fileToZip, zipedFile, null);
             return result;
         }
 
        /// <summary>
         /// 压缩文件或文件夹
         /// </summary>
         /// <param name="fileToZip">要压缩的路径</param>
         /// <param name="zipedFile">压缩后的文件名</param>
         /// <param name="password">密码</param>
        /// <returns>压缩结果</returns>
         public static bool Zip(string fileToZip, string zipedFile, string password)
         {
             bool result = false;
             if (Directory.Exists(fileToZip))
                result = ZipDirectory(fileToZip, zipedFile, password);
             else if (File.Exists(fileToZip))
                 result = ZipFile(fileToZip, zipedFile, password);
 
            return result;
        }

        /// <summary>
        /// 压缩文件或文件夹
       /// </summary>
         /// <param name="fileToZip">要压缩的路径</param>
         /// <param name="zipedFile">压缩后的文件名</param>
        /// <returns>压缩结果</returns>
        public static bool Zip(string fileToZip, string zipedFile)
        {
            bool result = Zip(fileToZip, zipedFile, null);
            return result;
 
        }
 
         #endregion

        #region 解压
 
         /// <summary>
         /// 解压功能(解压压缩文件到指定目录)
         /// </summary>
         /// <param name="fileToUnZip">待解压的文件</param>
        /// <param name="zipedFolder">指定解压目标目录</param>
         /// <param name="password">密码</param>
         /// <returns>解压结果</returns>
         public static bool UnZip(string fileToUnZip, string zipedFolder, string password)
        {
             bool result = true;
            FileStream fs = null;
            ZipInputStream zipStream = null;
            ZipEntry ent = null;
            string fileName;

            if (!File.Exists(fileToUnZip))
                 return false;

            if (!Directory.Exists(zipedFolder))
                Directory.CreateDirectory(zipedFolder);
 
            try
             {
                zipStream=new ZipInputStream(File.OpenRead(fileToUnZip));
                if(!string.IsNullOrEmpty(password))zipStream.Password=password;
                 while ((ent=zipStream.GetNextEntry())!=null)
                {
                     if (!string.IsNullOrEmpty(ent.Name))
                     {
                        fileName = Path.Combine(zipedFolder, ent.Name);
                    fileName = fileName.Replace('/', '\\');//change by Mr.HopeGi
 
                        if (fileName.EndsWith("\\"))
                        {
                            Directory.CreateDirectory(fileName);
                            continue;
                       }

                     fs = File.Create(fileName);
                        int size = 2048;
                       byte[] data = new byte[size];
                         while (true)
                         {
                             size = fs.Read(data, 0, data.Length);
                             if (size > 0)
                                 fs.Write(data, 0, data.Length);
                            else
                                 break;
                         }
                    }
                 }
             }
             catch
             {
                 result = false;
            }
            finally
             {
                if (fs != null)
                 {
                     fs.Close();
                    fs.Dispose();
                }
                 if (zipStream != null)
                {
                   zipStream.Close();
                     zipStream.Dispose();
                 }
                 if(ent!=null)
                 {
                     ent = null;
                 }
                 GC.Collect();
                 GC.Collect(1);
             }
             return result;
         }
 
         /// <summary>
         /// 解压功能(解压压缩文件到指定目录)
         /// </summary>
        /// <param name="fileToUnZip">待解压的文件</param>
         /// <param name="zipedFolder">指定解压目标目录</param>
        /// <returns>解压结果</returns>
        public static bool UnZip(string fileToUnZip, string zipedFolder)
         {
             bool result = UnZip(fileToUnZip, zipedFolder, null);
            return result;
         }
 
         #endregion
     }